Conventional earpiece auditory devices (e.g., earphones, headphones, headsets, monitors, IFB devices, hearing aids, earplugs, etc.) are often bulky and uncomfortable for a user to wear. In addition, typically, these devices are cosmetically undesirable. For example, generally, use of one of these conventional devices may be easily discovered through casual observation of the user. However, in some circumstances, users may not want others to know they are using an earpiece auditory device. For example, oftentimes hearing aid users do not want others to know they are using such devices. As another example, news anchors using IFB devices may not want the device to be seen on camera. Moreover, use of a bulky and noticeable earpiece auditory device may potentially have more serious consequences. For example, a bulky, noticeable earpiece auditory device may put plain-clothed security personnel at risk of being discovered.
To overcome these problems, earpiece auditory devices have been developed wherein the entire device may be placed behind the ear of the user or within the ear of the user. However such devices, although possibly reducing some of the conspicuousness of the device, create their own set of problems.
For example, placing an auditory device within the outer portion of an ear canal of a user may cause the user to experience the occlusion effect, which is a plugged sensation that results when the ear canal is blocked and air conduction is impeded by the introduction of at least a portion of an earpiece auditory device into the outer portion of the ear canal. The ear canal (sometimes referred to as the external auditory meatus) has two zones: an outer zone and an inner zone. The outer zone, sometimes referred to as the cartilaginous region, makes up approximately two-thirds of the total length of the ear canal. The inner zone, referred to as the bony portion, accounts for the remaining one third of the length of the ear canal. The earlier mentioned plugged sensation is the result of the acoustic energy created by the vibration of the walls of the outer portion of the ear canal in response to a bone conducted signal. H. Gustav Mueller, “CIC Hearing Aids” What Is Their Impact On The Occlusion Effect?”, The Hearing Journal, Vol. 47, No. 11, p. 29–35 (November 1994). This energy typically escapes when the ear canal is at least partially open. However, unfortunately, when an earpiece auditory device of sufficient size is placed in the outer portion of the ear canal, at least a portion of this energy is trapped in the user's ear, thereby causing the above described plugged sensation. In some existing earpiece auditory devices, a vent(s) or other means whereby bone-conducted energy may escape the ear canal is provided (e.g., the device is designed to leave the ear canal at least partially open), thereby minimizing or even eliminating the occlusion effect.
In addition, certain of the existing earpiece auditory devices (of both the behind the ear and within the ear or ear canal varieties) experience feedback problems. For example, some conventional earpiece auditory devices are designed with a microphone and speaker mounted to the same housing. As a result of such a design, the microphone and speaker are mechanically coupled to each other. One notably undesirable consequence of this mechanical coupling is electroacoustic feedback. Furthermore, in some conventional earpiece auditory devices, irrespective of the mounting of such components, a microphone and speaker of the device are situated in such close proximity to each other that feedback occurs. The above discussed feedback problems increase as the gain of the auditory device increases. As a result, the gain of such auditory devices are limited by the electroacoustic feedback.
In the past, efforts have been made to reduce such electroacoustic feedback by, e.g., physically separating the microphone and the speaker used in such devices. For example, The Volta Review January 1980, pp. 40–44, describes a hearing aid in which the receiver is separated from the main body of the aid and mounted in an ear mold that in turn is placed in the user's ear.
While such a design may result in reduced electroacoustic feedback, it would be commercially unacceptable. One reason for this is, similar to earlier discussions, the user will experience the occlusion effect on account of the introduction of the earmold into the outer portion of the user's ear canal.
In addition to the above, existing earpiece auditory devices are typically designed such that the electrical components of the device (e.g, the speaker, receiver, microphone, etc., or whichever of such components are included in the particular device) are coupled to each other via some fixed connection. For example, in at least one instance, a speaker of an earpiece auditory device is electrically coupled (either directly or indirectly) to a microphone, processing circuitry, and/or a transceiver of a device via some form of fixed wiring. Such fixed wiring is typically done because of the protection from moisture or other undesirable elements that such fixed wiring normally provides to electrical couplings. In addition, fixed wiring is used because it occupies little of the scarce device space.
However, as a result of such fixed couplings, assembly of the devices and/or replacement of defective or expired parts is normally costly, time-consuming, and/or burdensome. To illustrate, currently, when some element of an earpiece auditory device needs to be replaced (e.g., a part has expired or is defective), in most circumstances, the user must return the device to the manufacturer or send the device to a repair lab.
Moreover, in some circumstances, at the manufacturer or the repair lab, the device must be taken apart, the defective or expired part(s) carefully removed, and a replacement part or parts inserted into the device and fixed (e.g., soldered) into place. Under such a process, it is usually several days or weeks before the auditory device is returned to the user.
In addition, for some earpiece auditory devices (e.g., some hearing aids, some ear plugs), at least a portion of the earpiece auditory device is normally manufactured to the specific dimensions of a particular user's ear structure and/or the user's intended use for the earpiece auditory device, as determined during a fitting of the user by a technician, representative, salesperson, etc. Although there are some advantages to this procedure (e.g., providing a desired fit to a particular user), one notable disadvantage to customizing these devices in this manner, at least to a manufacturer, is that such devices can then not be mass produced.
Furthermore, another disadvantage of this customizing of portions of earpiece auditory devices to a particular customer's ear shape is that if, upon delivery to the user, it is discovered that the fit of the auditory device is deficient in some manner, as was the case with replacing defective or expired parts, replacement of the ill-fitting earpiece is costly, time-consuming, and burdensome.